Heat Exchangers (CH) - Johnson Controls - Metasys - LIT-12011147 - Software Application - Controller Configuration Tool - 16.0

Controller Tool Help

Brand
Johnson Controls
Metasys
Product name
Controller Configuration Tool
Document type
User Guide
Document number
LIT-12011147
Version
16.0
Revision date
2023-10-02
Language
English

Use this section for systems with Heat Exchangers.

The selection options for Heat Exchangers are:

  • Number of Heat Exchangers: This option is used to select the number of heat exchangers.

    • One

    • Two

      • With Isolation Valves: This option provides control for systems with isolation valves preventing flow through the heat exchangers when not in use.

        • Valve Open Status: This option monitors the status of the isolation valve.

  • Inlet Valve: This option is loaded for heat exchangers that are controlled by modulating an inlet valve.

    • Two Valves: This option provides control if the flow is split through two valves to increase control ability.

    • Return Water Low Limit Control: This option provides temperature control for the inlet return water. This process uses the supply water temperature to modulate the control valve. The inlet return water control overrides the primary control to prevent the inlet return water temperature from dropping below its limit.

  • Loop Mixing Valve: This option provides control if the loop supply temperature is controlled using a 3-way mixing valve.

  • HX Maintenance Switch: This option generates network inputs used to remove a heat exchanger from service.

    • Maintenance Switch (BI): This option generates binary inputs used to remove a heat exchanger from service.

  • Primary HW Pumps: This option is used to select the number of primary HW pumps.

    • One Pump

    • Two Pumps

    • Three Pumps

    • Variable Speed: This option is for variable primary flow. This selection varies the primary pump speed to maintain differential pressure in the hot water loop while simultaneously operating a bypass valve to maintain minimum flow through the heat exchangers. Selecting this option disables Secondary Variable Speed Hot Water Pumping.

    • Bypass Valve with Diff Pressure Sensor: This option allows a bypass valve to control differential pressure.

    • Pump Rotation (Runtime): This option automatically changes pump staging order based on runtime (equal runtime rotation strategy).

    • Pump Status: This option monitors the status of the pump.

      • Loss of Status Strategy

        • Automatic Restart

        • Manual Restart

          • Unit Reset Switch (BI)

    • Alarm Management

      • Lockout Switch

        • Lockout Switch (BI)

      • Motor Overload Tripped

        • Automatic Restart

        • Manual Restart

          • Unit Reset Switch (BI)

      • Frequency Converter Fault

        • Automatic Restart

        • Manual Restart

          • Unit Reset Switch (BI)

      • Belt Alarm

        • Automatic Restart

        • Manual Restart

          • Unit Reset Switch (BI)

    • Blocking Protection: This option provides monitoring of the command to a motor (typically a pump). If the command is off for an extended period of time (for example, 7 days), the motor starts for a short time (for example, 30 seconds). This feature prevents blocking (that is, it prevents the motor from seizing up).

    • Three Stage Frost Protection: This option provides 3 stages of frost protection. If the outdoor air temperature is less than the first setpoint, the primary pumps run (at medium flow for variable speed). If the outdoor air temperature continues to drop and goes below the second setpoint and the zone temperature is greater than or equal to the zone heating setpoint, the boiler turns on. If the outdoor air temperature is below the second setpoint and the zone temperature is less than the zone heating setpoint, the appropriate zone loop turns on.

If the Hot Water/Steam Boilers is selected, Heat Exchangers cannot be selected.